transitive verb(amerced; amercing)Etymology:Middle Englishamercien, from Anglo-Frenchamercier, from Old Frencha merci at (one's) mercyDate: 15th century
to punish by a fine whose amount is fixed by the court; broadlypunish
• amercementnoun
• amerciableadjective

amerce — (v.) 1215, earlier amercy, Anglo Fr. amercier to fine, from merci mercy, grace (see MERCY (Cf. mercy)). The legal phrase estre a merci to be at the mercy of (a tribunal, etc.) was corrupted to estre amercié in an example of how a legalese… … Etymology dictionary